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Dust extinction and the SDSS. 조정연 (J . Cho) ( 충남대 ). 1. Internal Extinction (effect of inclination). 2. Extinction by the ICM/Super-Galactic Plane. 3. Extinction by HVCs (high velocity clouds). cluster. HVC. Milky Way Galaxy.
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Dust extinction and the SDSS 조정연 (J. Cho) (충남대)
1. Internal Extinction (effect of inclination) 2. Extinction by the ICM/Super-Galactic Plane 3. Extinction by HVCs (high velocity clouds) cluster HVC Milky Way Galaxy
Topic 1: Internal Extinction in Spirals (effect of inclination)
Tully et al 1998 K: ~2.2mm R: ~700nm I: ~ 900nm Mag. after Galactic & k-corrections What causes the scatter? * Note: Insignificant absorption at K-band
Possible projects: • Repeat Tully et al 1998? Shao et al 2006? • Study the effect of concentration • Study the effect of inclination for bulge and disk separately • Study the effect of inclination for blue- and red-bulge • separately
Luminosity function Driver et al 07
Park & Choi (2005) spirals Calculate similar plots for bulge and disk separately?
Topic 2: Extinction by ICM/SGP Dust in galaxy clusters - IR emission detected (Stickel et al 1998; Cox et al 1998; Bregmann 1990)) * Mdust ~ 108-9 Msun - Extinction of UV objects behind Coma observed (Boyle et al 1998; Dwek et al 1990)
Possible projects • Color change by clusters • Change of number count?
Topic 3: Extinction by HVCs 1) High velocity clouds (HVCs) + Compact HVCs (CHVCs) * |VLSR| > 90 km/sec 2) Intermediate velocity clouds (IVCs) * 90 > |VLSR| > 30 km/sec
1) HVCs: - Muller et al (1963) : 1st detection in H21cm - |VLSR| > 90 km/sec - low metallicity (~0.1 solar for Complex C; ~0.3 for the Magellanic Stream) - catalog: Wakker & van Woerden (1991) - failed CO detection: Wakker et al (1997) C Magellanic Stream Mivillie-Deschenes (2006)
Compact HVCs • -Angular size: < 2o • Braun & Burton (1999): 66 CHVCs • -de Heij et al (2002): 67 CHVCs • Putman et al (2002): 179 CHVCs • de Heij et al (2002b): 216 CHVCs • -origin? • Blitz et al (1999): far away (~1Mpc) massive (~107 Msun) • dark matter clouds? • *problem: Recent measurements indicate • that distance ~ 10 kpc • Infall of low metallicity gas from intergalactic space? • Galactic fountain? • Observation of chemical composition is crucial • * Do they have star formation? Do they have molecules?
2o ~1Mpc Blitz (1999) : Massive satellites Falling primordial gas Galactic fountain
They do contain dust grains clumpy structures? Complex C Mivillie-Deschenes et al (2005)
2) IVCs - 90>|VLSR| > 30 km/sec - metallicity : 0.5 ~ 1 solar - catalog: Kuntz & Danly (1996) also Wakker (2001) - a few CO observations
Weiss et al (1999): CO observation CO CO CO See also Mebold et al 1985 Heiles, Reach, & Koo 1988 Desert, Bazell & Blitz 1990
Systematic studies of dust in IVCs will be useful This is HI map
Conclusion • Possible projects • Effect of inclination • Dust in the ICM • Dust in HVCs/IVCs